Question: Complete the recursive formula of the geometric sequence $16\,,\,3.2\,,\,0.64\,,\,0.128,...$. $a(1)=$
Answer: The first term is $16$ and the common ratio is $\dfrac15$. ${\times\dfrac15\,\curvearrowright}$ ${\times\dfrac15\,\curvearrowright}$ ${\times\dfrac15\,\curvearrowright}$ $16,$ $3.2,$ $0.64,$ $0.128,...$ This is the recursive formula of $16\,,\,3.2\,,\,0.64\,,\,0.128,...$. $\begin{cases} a(1)=16 \\\\ a(n)=a(n-1)\cdot\dfrac15 \end{cases}$